Project 1 Mechanical design of battery pack
Battery pack capacity: 18 kWh
Cell: ANR26650M1-B
Prepare a detailed battery pack its enclosure. State your assumptions.
ans -
Cell: ANR26650M1-B specifications
calculations with some assumptions
ANR26650M1-B Specifications
Nominal Ratings
Voltage: 3.3 Volts
Capacity: 2.5 Ah
Energy: 8.25 Wh
Specific Power: 2600 W/kg
Impedance (1KHz AC Typical) 6 mΩ
Cycle Life at 1C/1C, 100% DOD: > 4000 cycles
Cell Type: 26650 Lithium Ion Power Cylindrical Cell
Discharging
Max Continuous Discharage: 50 A
Max Pulse Discharge Current >50% SOC (10s): 120 A
Minimum Voltage: 2 Volts
Temperature: -30ºC to 55ºC
Charging
Recommended Standard Charge: 2.5 Amps
Max Charge Rate: 10 Amps
Max Pulse Charge Current <50% SOC (10s): 25 A
Float Voltage: 3.45 Volts
Recommended charge V & Cut-off Current: 3.6 Volts, taper to 125mA
Temperature
(reduce charging current to 250mA when under 0ºC): 0ºC to 55ºC
Mechanical
Diameter: Ø25.96 +/- 0.5 mm (1.0")
Length: 65.15 +/- 0.5 mm (2.6")
Mass: 76 g
Calculation assumptions:- 18kWh Battery Pack
calculation designing 18kWh battery pack energy require to vehicle its proper range is depending voltage (V) parameter ampere-hour or capacity (Ah).
design high voltage battery pack electric vehicle range up to 220 km. 145.2 V a nominal voltage series connection.
the volume of the cell used to find out the total volume of the battery pack.
- Single Cell Energy (Wh)
= Cell Capacity (Ah) x Cell Voltage (V)
= 2.6 x 3.3
= 8.58 Wh
value of single cell is calculate total energy of the battery pack.-Single Cell Energy Density
Volumetric energy (Wh/m^3) = Single Cell Energy / Volume of each cell
= 8.58 Wh / 0.03451 m^3
= 248.62 Wh/m^3
Gravimetric energy (Wh/kg) = Single Cell Energy / Single Cell Mass
= 8.58 Wh / 0.076 kg
= 112.89 Wh/kg
Calculation of High Voltage Battery Pack
calculation of battery pack a vehicle to achieve 250 km, 18 kWh battery pack. Also, 145.2 nominal voltage for series connection.
Vehicle Range = 250 KM (assumed)
Battery Pack capacity = 18.121 kWh or 18120.96 Wh (For better and accurate calculation here I change kWh)
We will calculate per km average energy = 18120.96 / 250
= 72.483 Wh/km
Therefor,
Battery Pack total energy = Average energy x km
= 72.483 x 250
= 18120.96 Wh or 18.120 kwh
Nominal voltage for series connection = 145.2 V, Basically the motor power value according to the motor.
- Number of cells connected series
= Nominal voltage of series connection / Nominal voltage of a single cell
=145.2 V / 3.3 V
= 44
44 Cells connected in series connection provide a proper voltage.
- Energy for battery pack (wh)
= No. of cells connected in series x Single-cell energy
= 44 x 8.58 wh
= 377.52 wh
-- Number of cells connected in parallel
= Battery pack total energy (wh) / Energy for battery pack (wh)
=18120.96/377.52
= 48
48 cells will be connected in parallel to provide a proper capacity power.
-- Battery pack total energy (wh)
= No. of cells connected in parallel x Energy for battery pack (wh)
= 48 x 377.52
= 18120.96 wh or 18.120 kWh
-- Battery pack capacity
= No. of cells connected in parallel x Single cell capacity (Ah)
= 48 x 2.6 Ah
= 124.8 Ah
The battery pack capacity is total power required by the vehicle.
-- Total number of cells for battery pack
= No. of cells connected in parallel x No. of cells connected in series
=48x44
= 2112
2112 Cells a complete battery pack.
-- Mass of battery pack
= Total no. of cells for batter pack x Mass of single cell
= 2112 x 0.076 kg
= 160.512 kg
total weight of cells connected in parallel and series.
-- Total volume of the battery pack
= Total no. of cells for batter pack x Volume of single cell
= 2112 x 0.0345
= 72.89 m^3
This is the volume of2112 cells which are used in the battery pack system.
-- Cell peak current (A)
= C rate (Max Pulse Charge Current) x Single cell capacity
= 20 x 2.6
= 52 A
-- Battery pack peak current (A)
= Cell peak current x No. of cells connected in parallel
=52X48
= 2496 A
operation of the battery pack. a vehicle decide power is required to move.
-- Battery pack peak power (W)
= Battery pack peak current x Voltage of series connection
= 2496 A x 145.2
= 3624192 or 362.42 W
-- Cell continuous current (A)
= Crate (Max Continuous Charge Current) x Single cell capacity
= 10 x 2.6
= 26 A
-- Battery pack continuous current (A)
= Cell continuous current x No. of cells connected in parallel
= 26 x 48
= 1248 A
power which is supply continue whole battery pack system.
-- Battery pack continuous power (W)
= Battery pack continuous current x Voltage of series connection
=1248 x145.2
= 18120.96 or 18.120 Kwh
detailed battery pack drawing along with its enclosure.
BATTERY HOLDER ,SPACER For CELL CYLINDRICAL LI-ION
Nickel Strips
Nickel strip is battery building. efficiency of usage in spot welding and soldering as well high corrosion resistance over time good properties and excellent resistance to many corrosive environments. The pure nickel will never get rust after it applied to battery packs. It won’t affect the current transfer between batteries.
Pure nickel strips material you want buymany vendors swap out it for nickel-plated steel strips, poorer greater resistance – not suitable most battery projects.
100% pure nickel strip. high-quality pure nickel.solder incredibly quickly, weld them your existing busbar connections supply current pull through the busbars. The benefits nearly limitless!
battery enclosure
Design Benefits
- Up to 50 percent lighter than an equivalent steel design
- Best-in-class mass energy density at more than 160
watt-hours per kilogram, an extremely efficient design
for OEMs and Tier 1 battery pack manufacturers.
- Accommodates all battery cell types and is designed
particularly for battery electric vehicles with larger
power packs such as pick-up trucks, sport utility
vehicles and crossovers.
- Most cost-effective aluminum solution for mass
production electric vehicles when compared to
aluminum extrusion and casting-intense designs.
- Low price premium on $/kg saved compared
to equivalent steel designs at substantially
lower weight.
Power (p)= Voltage (v) * Current (i) kw
3.3 *2.5 =8.25 kw
18kwh , 48s 48p
i.e; 48*48 =2304 cells
series connection 48*3.3 =158.4 v
parallel connection 48* 2.5 =120 A
158.4* 120 =19.008 kwh energy or capacity. design battery pack 48s ,48p cell along wth battery spacers to hold cells connection nickel strip is used
cells connected nickel strip spot welding cell not get damage.
final form